The present invention relates generally to a technique for rebuilding a head stack assembly used in a magnetic disk drive. More particularly, the present invention relates to a technique for removing a defective head gimbal assembly from the head stack assembly and replacing the defective head gimbal assembly with a good one without allowing any good head gimbal assemblies to be damaged.
A magnetic disk drive uses a head gimbal assembly (hereinafter abbreviated to an “HGA”) and a carriage. The HGA includes a magnetic head/slider and a suspension. The carriage includes an actuator arm and a voice coil. The suspension assembly of the HGA includes a flexure allowing the head/slider to make a flexible pivot motion, or what is also called as a gimbal motion. The suspension assembly further includes a load beam for supporting the flexure and a hinge for giving a pressing load to the load beam.
A mount plate is secured to the HGA. The HGA is secured to the actuator arm of the carriage through swaging of the mount plate. An assembly including the carriage and the HGA is called a head stack assembly (hereinafter abbreviated to an “HSA”). A number of HGAs corresponding to the number of recording surfaces of a magnetic disk are incorporated into the HSA. A defect may at times be detected in a specific HGA when a variety of functional tests are carried out after the magnetic disk drive has been assembled. This makes it necessary to replace the defective HGA with a good HGA, thereby rebuilding the HSA.